In chemical process technology, it is necessary to continuously or intermittently measure a number of parameters. Such parameters include, for example, the pH value, the redox potential, the conductivity, the contents of free or dissolved oxygen and the concentrations of other components dissolved in the liquid. The measurement of these parameters in suspensions always involves some difficulties and these difficulties may increase in the case that the suspensions contain contaminating, sticking or crystallizing components. Rapidly agitated suspensions cause abrasion to the equipment and erroneous measurements may be obtained on the measuring probes.
Typically, prior art devices attempt to alleviate the above problems by passing a portion of the suspension through a quiescent-flow vessel, having probes therein for measuirng the desired parameters. However, there is a drawback with such devices, in that they clog relatively easily and have to be replaced or cleaned rather often.